IEC 61158-3-12:2010 provides common elements for basic time-critical messaging communications between devices in an automation environment. It defines in an abstract way the externally visible service provided by the Type 12 fieldbus data-link layer in terms of:
- the primitive actions and events of the service;
- the parameters associated with each primitive action and event, and the form which they take;
- the interrelationship between these actions and events, and their valid sequences. This second edition cancels and replaces the first edition published in 2007. It constitutes a technical revision. The main changes with respect to the previous edition are editorial improvements. This bilingual version published in 2011-11, corresponds to the English version published in 2010-07.